Few would agree. Its admirers seem to be, well, MS-Windows users, since WP 9 is pretty much the Win32 version recompiled to run in a Winelib environment, with RAM bloat, stability problems, and other glitches (including DOS drive letters in file dialogues!) that are routine on MS-Windows but not Linux.
Very likely, WP 9 introduced some feature-set attractions, but needing to run emulation code with performance and stability problems seems a poor trade-off. I consider 8.1 vastly preferable.
My best guess: Doing a Winelib version allowed Corel to leverage its existing Win32 codebase, write a minimum amount of new code, shorten development time, reduce costs, and keep the effort in-house rather than having to hire SD Corp. again.
You can substitute an improved version of Corel's fork of the WINE emulation code ("Corelwine"), which was for a while maintained by Michael Torrie, at http://web.archive.org/web/20040213000457/students.cs.byu.edu/~torriem/corelwine/, with other possibly useful pages at http://panopticon.csustan.edu/thood/corel-wp9.txt and http://web.archive.org/web/20040225112645/http://members.chello.at/hrdisk/corelwine.html.
I can't guarantee the truth of this account, but I've heard claims that Corel deferred submission of its patches to the WINE Project development team so long that they could no longer be merged when they arrived, leading to inadvertent creation of a separate development fork, dubbed "Corelwine". This is the codebase that Torrie maintained and updated, separately from the WINE Project's flagship codebase.
Moreover, Corelwine was built to be dependent on Bitstream, Inc.'s proprietary Fontastic font server, a feature unlikely to be included in the WINE Project code of the day, and now precluded by WINE licensing. (Reportedly -- see post by "gavriels" = Gavriel States -- Corel decided to use Fontastic to skirt likely font-patent problems, which indeed have subsequently plagued authors of open-source font software.)
There are also some remaining updates to WP9 / WP Office 2000 inside ftp://ftp.corel.com/pub/linux/Office2000/updates/ and ftp://ftp.corel.com/pub/linux/Graphics9/updates/. Among those updates, the revised WP Office 2000 installer available there is essential for most modern Linux distributions to make the Fontastic font server install correctly. Note that you need at least one printer configured before installation. However, versions of Corelwine available through September 2004 (and thus also WP9) break completely on any system with glibc 2.3.2 or above, i.e., on essentially all current Linux distributions. Efforts to fix Corelwine are underway. See FAQ section "WP9 stopped working / won't install..." for details.
Because online resources for WP9 for Linux (also PhotoPaint9 and the other WP Office 2000 components) have been disappearing, I've been gathering and archiving them inside http://linuxmafia.com/pub/linux/apps/. You may find what you need there.
It's sometimes available for US $49 from Surplus Computers of Santa Clara, California at http://www.surpluscomputers.com/. EMS Professional Software and Consulting, http://www.emsps.com/oldtools/wp.htm, sometimes has the Deluxe Edition. (Inquire for pricing.) Both editions (Standard and Deluxe) of WP Office 2000 for Linux are frequently offered on eBay.